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2 commits

Author SHA1 Message Date
Ken Sedgwick
c7fa9bd662
SetConfigHandler: fail setconfig when the owner rejects the value
setconfig was acknowledged with unconditional success after
broadcasting Msg::Option, while owning modules reject bad values by
log-and-keep.  lightningd persists a setconfig value (configvar_save)
only on a success response, so the blanket ack recorded values clboss
never applied: listconfigs and config.setconfig diverged from the
running configuration, and a non-numeric value persisted for an
int-typed option fails lightningd's own option parse on the next
start -- lightningd refuses to boot.

Add a rejection back-channel to Msg::Option: SetConfigHandler
allocates a shared reject_reason (null on init-time raises, so
aggregate initialization at existing sites is unaffected), the owning
subscriber reports rejection via the new Msg::Option::reject() helper
(a no-op at init time, where quietly keeping the default is right),
and SetConfigHandler -- whose bus.raise() returns only after all
subscribers ran -- fails the command with invalid-params when a
reason was set.  All dynamic-option owners in this tree report their
rejections: RebalanceModeManager (unrecognized mode), FundsMover's
three numeric handlers, and AskreneUpdates' shared age/retain
handler.
2026-08-04 11:01:56 -07:00
Ken Sedgwick
e00758aac3
Add rebalancer mode selector (classic/off) as a dynamic option
Introduces a single source of truth for which rebalancing track is
active.  Boss::Mod::RebalanceModeManager owns the mode in memory (no
sqlite, so a restart reverts to the configured default, giving a
known-good baseline on every boot) and registers clboss-rebalance-mode
as a dynamic option: the config file sets the startup default and
`setconfig clboss-rebalance-mode <mode>` switches it at runtime without
a restart.  It answers RequestRebalanceMode queries and reports the mode
under clboss-status.

Modes are "classic" (run the rebalancer) and "off" (a real quiesce,
also the supported way to disable rebalancing entirely).  This is the
seam that later lets a second rebalancing track coexist and be toggled
without a restart.

The classic-track rebalancers self-gate on the mode at their existing
decision points, modeled on RebalanceUnmanager: EarningsRebalancer gates
its trigger, InitialRebalancer gates its run, and JitRebalancer gates
the top of htlc_accepted so that in off mode it does not defer the HTLC
and adds no forwarding latency.  A header-only Boss::ModG::
RebalanceModeProxy provides get_mode for the gate sites.  off composes
with the existing per-peer unmanage balance tag: off wins globally,
otherwise the per-peer tag still excludes specific peers.

The three rebalancers' unit tests now install a RebalanceModeManager on
the test bus so the self-gate query is answered (default classic, so
they behave as before).  Without a responder the RequestRebalanceMode
ReqResp is never satisfied and leaks, which the valgrind-checked tests
flag as a failure.

New files: Boss/RebalanceMode.hpp, Boss/Msg/RequestRebalanceMode.hpp,
Boss/Msg/ResponseRebalanceMode.hpp, Boss/ModG/RebalanceModeProxy.hpp,
Boss/Mod/RebalanceModeManager.{hpp,cpp}.
2026-08-04 11:01:46 -07:00